igneous
Basalt
Extrusive mafic igneous rock
AI-generated identification · may be incorrectHardness of 6 on Mohs scale, dark gray to black color, aphanitic texture, and dull luster.
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Physical properties
Hardness of 6 on Mohs scale, dark gray to black color, aphanitic texture, and dull luster.
Formation & geological history
Formed from the rapid cooling of low-viscosity basaltic lava exposed at or very near the Earth's surface.
Uses & applications
Commonly used in construction, road aggregates, and production of stone wool insulation.
Geological facts
Basalt is the most common rock type in the Earth's crust underlying the world's ocean basins and forms massive features like the Columbia River Plateaus.
Field identification & locations
Identified by its dark, fine-grained groundmass, often containing small visible crystals of olivine or pyroxene.
